Steerable medical device

ABSTRACT

A medical device and a system including same are provided. The medical device includes an elongated device body, at least a portion of which is steerable within a body of a subject via at least one control wire; and a plurality of control wire guides disposed along the elongated device body and being deployable to deflect the at least one control wire away from a longitudinal axis of the elongated device body.

RELATED APPLICATIONS

This application is a National Phase of PCT Patent Application No.PCT/IL2014/050224 having International filing date of Feb. 17, 2014,which claims the benefit of priority under 35 USC § 119(e) of U.S.Provisional Patent Application No. 61/765,745 filed on Feb. 17, 2013.The contents of the above applications are all incorporated by referenceas if fully set forth herein in their entirety.

FIELD AND BACKGROUND OF THE INVENTION

The present invention relates to a steerable medical device and, moreparticularly, to a medical device which includes radially deployablecontrol wire guides.

Medical devices such as endoscopes and catheters are widely used inminimally invasive surgery for viewing or treating organs, cavities,passageways, and tissues. Generally, such devices include an elongateddevice body which is designed for delivering and positioning adistally-mounted instrument (e.g. scalpel, grasper or camera/cameralens) within a body cavity, vessel or tissue.

Since such devices are delivered though a delivery port which ispositioned through a small incision made in the tissue wall (e.g.abdominal wall), and are utilized in an anatomically constrained space,it is desirable that the medical device or at least a portion thereof besteerable, or maneuverable inside the body using controls positionedoutside the body (at the proximal end of the medical device). Suchsteering enables an operator to guide the device within the body andaccurately position the distally-mounted instrument at an anatomicallandmark.

In order to control deflection of a steerable portion of the device andthus steer the instrument mounted thereon, steerable medical devicestypically employ one or more control wires which run the length of thedevice and terminate at the distal end of the steerable portion or atthe distal tip.

The proximal end of each control wire is connected to the user operatedhandle; pulling of the wire bends the device body and deflects thesteerable portion with relation the pulled wire.

Numerous examples of steerable devices are known in the art, see forexample, U.S. Pat. Nos. 2,498,692; 4,753,223; 6,126,649; 5,873,842;7,481,793; 6,817,974; 7,682,307 and U.S. Pat. Application PublicationNo. 20090259141.

Although prior art devices can be effectively steered inside the body,the relatively small diameter of the elongated device body (which isdictated by the diameter of the delivery port), severely limitsangle-of-deflection capabilities and increases the pull force requiredto deflect the steerable device portion.

As such, it would be highly advantageous to have a steerable medicaldevice having a device body narrow enough for delivery through standarddelivery ports and yet capable of providing wide angle steering of thedeflectable portion within the body while minimizing the pull forcerequired for such steering.

SUMMARY OF THE INVENTION

According to one aspect of the present invention there is provided amedical device comprising: (a) an elongated device body, at least aportion of which being steerable within a body of a subject via at leastone control wire; and (b) a plurality of control wire guides disposedalong the elongated device body, the wire guides being deployable todeflect the at least one control wire away from a longitudinal axis ofthe elongated device body.

According to further features in preferred embodiments of the inventiondescribed below, at least a portion of the elongated device body iscomposed of a plurality of segments.

According to still further features in the described preferredembodiments the control wire guides form a part of the segments.

According to still further features in the described preferredembodiments the control wire guides extend radially outward when theplurality of interlinked segments are longitudinally compressed.

According to still further features in the described preferredembodiments the medical device further comprises a tube for compressingthe interlinked segments.

According to still further features in the described preferredembodiments the control wire guides are attached to an external surfaceof the elongated device body.

According to still further features in the described preferredembodiments the control wire guides are struts capable of pivoting awayfrom a longitudinal axis of the elongated device body.

According to still further features in the described preferredembodiments the pivoting of the struts is effected by pulling of the atleast one control wire.

According to still further features in the described preferredembodiments the medical device further comprises a tubular sheath forcompressing the struts against the elongated device body, whereinremoval of the sheath releases the struts to pivot away from alongitudinal axis of the elongated device body.

According to still further features in the described preferredembodiments the medical device further comprises a plurality of controlwires, each being for deflecting the at least a portion of the elongateddevice body in a specific direction.

According to still further features in the described preferredembodiments each of the plurality of control wires is deflectable via aspecific set of control wire guides of the plurality of control wireguides.

According to still further features in the described preferredembodiments a number, spacing and/or deflection distance of control wireguides of the specific set of control wire guides varies for each of theplurality of control wires.

According to still further features in the described preferredembodiments the plurality of segments are interlinked.

According to still further features in the described preferredembodiments the elongated device body includes a flexible tubepositioned through each of the plurality of segments.

According to still further features in the described preferredembodiments the medical device further comprises a tissue manipulatorattached to a distal end of the elongated device body.

According to still further features in the described preferredembodiments the tissue manipulator is a grasper, a tissue cutter, or aneedle.

According to another aspect of the present invention there is providedmedical system comprising: (a) a first medical device having anelongated device body, at least a portion of the elongated device bodybeing characterized by a first cross sectional shape; (b) a secondmedical device having an elongated device body, at least a portion ofthe elongated device body being characterized by a second crosssectional shape; wherein the first cross sectional shape and the secondcross sectional shape are selected so as to maximize packing of at leastone of the first medical device and at least one second medical devicewithin an over tube.

According to still further features in the described preferredembodiments a portion of the elongated device body of the first medicaldevice and/or the second medical device is steerable within a body of asubject.

According to still further features in the described preferredembodiments the over tube is used for delivering the first medicaldevice and the second medical device into a body cavity.

According to still further features in the described preferredembodiments each of the first medical device and the second medicaldevice further comprises a tissue manipulator attached to a distal endof the elongated device body.

According to still further features in the described preferredembodiments the tissue manipulator of the first medical device isdifferent than a tissue manipulator of the medical device.

According to another aspect of the present invention there is provided amethod of treating a subject: (a) delivering the medical device of claim15 or the medical system of claim 20 into a body of the subject; and (b)using the tissue manipulator to surgically manipulate a target tissuethereby treating the subject.

The present invention successfully addresses the shortcomings of thepresently known configurations by providing a steerable medical devicehaving a deflectable region being configured capable of angling morethan 180 degrees with respect to a longitudinal axis of the device.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. Although methods and materialssimilar or equivalent to those described herein can be used in thepractice or testing of the present invention, suitable methods andmaterials are described below. In case of conflict, the patentspecification, including definitions, will control. In addition, thematerials, methods, and examples are illustrative only and not intendedto be limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is herein described, by way of example only, withreference to the accompanying drawings. With specific reference now tothe drawings in detail, it is stressed that the particulars shown are byway of example and for purposes of illustrative discussion of thepreferred embodiments of the present invention only, and are presentedin the cause of providing what is believed to be the most useful andreadily understood description of the principles and conceptual aspectsof the invention. In this regard, no attempt is made to show structuraldetails of the invention in more detail than is necessary for afundamental understanding of the invention, the description taken withthe drawings making apparent to those skilled in the art how the severalforms of the invention may be embodied in practice.

In the drawings:

FIGS. 1A-B illustrate one embodiment of the device of the presentinvention in delivery (FIG. 1A) and deployed (FIG. 1B) states.

FIGS. 2A-B illustrate another embodiment of the device of the presentinvention showing a single segment with control wire guides in adelivery state (FIG. 2A) and a deployed device (FIG. 2B).

FIGS. 3A-C illustrate another embodiment of the device of the presentinvention showing a single segment with control wire guides in adelivery state (FIG. 3A), a single segment in a deployed state (FIG. 3B)and a segment configuration that includes a return spring (FIG. 3C).

FIGS. 4A-C illustrate a tissue grasper device composed of the segmentsshown in FIGS. 3A-B, shown in a delivery state (FIG. 4A), a deployedstate (FIG. 4B), and a deflected state (FIG. 4C).

FIGS. 5A-B illustrate a device having 2 separately deflectable regionswhich can be deflected in the same direction (FIG. 5A) or in oppositedirections (zigzag, FIG. 5B).

FIGS. 6A-D illustrate a system which includes several steerable devicesconfigured for packing into a delivery tube. FIG. 6A is a cross sectionshowing arrangement of the devices in the delivery tube; FIGS. 6B-Cillustrate 2 configurations of steerable devices; and FIG. 6Dillustrates coordinated use of several devices co-delivered through adelivery tube.

FIGS. 7A-E illustrate deployment (FIGS. 7A-D) and steering (FIG. 7E) ofa prototype device constructed in accordance with the teachings of thepresent invention.

FIGS. 8A-B illustrate one embodiment of the present device showing theinternal components of a handle (FIG. 8A), and the handle attached tothe proximal end of the elongated body of the present device (FIG. 8B).

FIGS. 9A-B illustrate a prototype of one configuration of the presentdevice.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is of a medical device and system which can beused in minimally invasive surgery. Specifically, the present inventioncan be used to provide enhanced steering.

The principles and operation of the present invention may be betterunderstood with reference to the drawings and accompanying descriptions.

Before explaining at least one embodiment of the invention in detail, itis to be understood that the invention is not limited in its applicationto the details set forth in the following description or exemplified bythe Examples. The invention is capable of other embodiments or of beingpracticed or carried out in various ways. Also, it is to be understoodthat the phraseology and terminology employed herein is for the purposeof description and should not be regarded as limiting.

Steerable medical devices for use in minimally invasive surgery are wellknown in the art. Such devices typically utilize one or more controlwires operable from a proximal end of the device positioned outside thebody to deflect and thus steer a distal portion of the device positionedwithin the body. In order to enable the control wire to efficientlydeflect the distal portion of the device, the longitudinal axis of thecontrol wire must be offset from the axis of deflection. In general, thegreater the offset, the more deflection can be achieved with lesspulling force applied to the control wire.

Since the diameter of minimally invasive devices is dictated by thedelivery port used to gain access to the intrabody tissues (typically 5,8 or 10 mm), the offset between the control wire and the deflection axisis in fact limited by the diameter of such port and the configuration ofthe device.

To overcome this limitation, the present inventor has devised a uniquecontrol wire guide configuration which enables greater separationbetween the longitudinal axis of the control wire and the deflectionaxis of the device thus enabling greater deflection while greatlyreducing the pulling force required to achieve such deflection.

Thus, according to one aspect of the present invention there is provideda medical device which includes a steerable intrabody portion capable ofbeing steered through a wide range of angles (up to 180 degrees andmore) and patterns such as zigzag or varied diameter curves at one ormore points along its length.

As used herein, the phrase “medical device” refers to any deviceutilizable in treatment of a subject, preferably a human subject. Themedical device of the present invention is preferably used in minimallyinvasive surgery wherein a steerable distal portion thereof positionedwithin a body of a subject is controlled from a proximal end positionedoutside the body (extra corporeally) via a control mechanism whichpreferably includes control wires. The medical device can be used forviewing or for manipulating tissues within any body cavity. Examples ofmedical devices which can benefit from the present invention include anendoscope (e.g. laparoscope or thorascope), a catheter, a needle holder,grasper, Scissors, hook, stapler, retractor and the like.

The medical device of the present invention includes an elongated devicebody having a distal portion at least a portion of which is steerablewithin a body of a subject (also referred to herein as steerableportion), preferably via at least one control wire. As is furtherdescribed herein, the steerable portion of the device can be deflectedin various directions and configurations, e.g. the entire steerableportion can be deflected (arced) towards one direction using a singlecontrol wire, or a first segment of the steerable portion can bedeflected in one direction while another can be deflected in an oppositedirection (zigzag) using two or more control wires.

The elongated device body includes a plurality of control wire guidesdisposed along its length for routing one or more control wires from aproximal end of the elongated device body (which includes user controls,e.g. motorized or manual handle) to an end of a steerable portionthereof. In the case of a device which includes two or more separatelysteerable portions (e.g. zigzag-shaped deflection), each control wire isrouted to an end of a respective steerable portion.

In any case, at least some of the control wire guides are deployable todeflect a control wire carried thereby away from a longitudinal axis ofthe elongated device body. Deflection of the control wire away from thelongitudinal axis of the device (radially outward) increases the offsetbetween the control wire and the deflection axis of the elongated devicebody and thus provides a wider range of deflection angles whileminimizing the pulling force needed to achieve deflection.

As is described in detail below, the elongated device body is configuredsuch that deployment of the control wire guides can be effected by auser following insertion of the distal portion of the device into thebody. This enables delivery of the medical device of the presentinvention through a standard delivery port (e.g. 5, 8 or 10 mm trocarport).

Several configurations can be used to enable deflection of the controlwire away from the longitudinal axis of the elongated body. Suchconfigurations preferably utilize control wire guides that move radiallyoutward while also spacing the wire guides away from each other alongthe length of the elongated body. As is further described hereinbelow,such spacing increases the angulation capabilities of the elongatedbody.

Referring now to the drawings, FIGS. 1a-5b illustrates severalconfigurations of the present medical device which is referred to hereinas device 10.

FIGS. 1a-b illustrate an embodiment of device 10 which employs controlwire guides configured as fold-out struts.

Device 10 of FIGS. 1a-b includes an elongated device body 12 (alsoreferred to herein as elongated body 12 or body 12) which can include adeflectable portion 23 fabricated from a flexible tube or rod, or aseries of segments 13 (as shown in FIG. 1a-b ).

Elongated device body 12 includes a user operable handle (see FIGS. 8a-bfor an example) attached to proximal end thereof and an effector end(e.g. tissue manipulator such as a grasper) attached to a distal end (44in FIGS. 4a-5b ). The handle functions in controlling and setting anorientation and position of elongated body 12 and in operating theeffector end.

A flexible tube/rod configuration of deflectable portion 23 can befabricated from a polymer such as structural engineering polymer,polypropylene, polycarbonate and the like using molding or extrusiontechniques. In order to increase the maximal deflection angle,deflectable portion 23 can also include cutouts along one or more sidesof the tube (e.g. such as those shown in U.S. Pat. No. 4,911,148).

Elongated body 12 can be 20-40 cm in length and 2.5-12 mm in diameter.Elongated body 12 can be hollow or solid depending on the use of device10. For example, in cases where device 10 is used to steer an endoscopiccamera, elongated body 12 can be hollow in order to enable routing ofwires or fiber optic cables from a user operable end (handle) to acamera or lens mounted on a distal end of elongated device body. Ahollow elongated body 12 can also be used to route wires for controllingan operation of a tissue manipulator head such as a grasper although itwill be appreciated that such wires can also be routed on the externalsurface of elongated body 12 through dedicated guides.

Elongated body 12 also includes two or more control wire guides 18 whichin this embodiment of device 10 are configured as pivoting struts 20 (5shown). Struts 20 can be fabricated from a polymer or alloy and can beattached to elongated body 12 using well known approaches.Alternatively, struts 20 can be co-formed with elongated device body 12by, for example, cutting out struts 20 from the sidewall of atube-shaped elongated body.

Struts 20 are folded against elongated body 12 (as shown in FIG. 1a )during delivery of device 10 through a delivery port and are capable offolding out and back to assume a deployed position (as shown in FIG. 1b) in which struts 20 are angled at about 90 degrees with respect toelongated device body 12. Struts can be connected to elongated body 12via an elastic or pivoting hinge 27; a backstop can be provided onelongated body 12 to stop backward movement of strut 20 at about 90degrees, or alternatively, the hinge can be designed for such purposes.

Struts 20 can be maintained folded against device body via a deliveryover-tube or sheath or via a fastening mechanism. Alternatively, struts20 can be spring loaded to assume a folded configuration. Struts 20include holes 22 at a distal end thereof (2 shown for each strut 20)through which a control wire 24 (a pair of control wires 24 shown foreach strut) can be threaded.

Control wires 24, which can be threaded through one or more rows ofstruts 20 (one row shown). One or more control wires 24 (two shown),threaded from the user handle through a single row of struts 20(positioned on one side of elongated body 12 in the embodiment of FIGS.1a-b ) to an attachment point 21 at an end of the steerable portion,enables single-sided deflection (towards the side of struts 20) of asteerable portion of elongated body 12. Two or more control wires 24threaded through two opposing rows enable bi-directional deflection. Anynumber of control wires can be used depending on the deflectiondirection and configuration desired. A device 10 having severaldeflectable portions each separately capable of bi-directionaldeflection is described hereinbelow with reference to FIGS. 5a -b.

Each strut 20 has a length L and a distance D from an adjacent strut 20(FIG. 1b ). Length L can be for example in the range of 1-5 mm, whereasdistance D can be for example anywhere from 3 to 6 mm. Length Ldetermines a leverage provided by strut 20 on a deflection point orregion in elongated body 12 (for example, a point in a center of a widthof elongated body 12 between segments 13), a larger L provides moreleverage since the distance between the wire supported by strut 20 andthe center of elongated body 12 is larger. Distance D determines themaximum angle of deflection of elongated body 12 (from the longitudinalaxis) at the region of struts 20, a larger D enables a larger angle ofdeflection since contact between the tips of struts 20 will preventfurther deflection.

The force needed to angle the links of a steerable segment of device 10depends on the elastic properties of the steerable segment, and thedistance between control wire 24 and a width center point of thesteerable segment. This distance increases from length d to length Dwhen struts 20 are deployed. The ratio d/D indicates the reduction inforce needed to angle the links of a steerable segment.

For example: in simple joint of regular tool having shaft with 5 mmdiameter with typical length ofd=2.2_(mm)

If, for example, the force needed to angle the steerable segment isF=10_(N), then the moment of angulation can be calculated by:M bending=F×d _(regular shaft)M bending=10_(N)×0.022_(M)M bending=0.22_(NM)

If, for example, distance D is 6.6 mm, and the elastic properties of thesteerable segment remain the same then the force needed to angle thesteerable segment be calculated by:M bending=F×D _(struts folded out)0.22 NM=F×0.066_(M)F=0.22_(NM)/0.066_(M)F=3.33_(N)

Device 10 can be deployed by pushing it out of the over-tube within thebody cavity, or alternatively, in the case where struts 20 are fastenedto, or spring-loaded against, elongated body 12, pulling of controlwires 24 can release struts 20 and unfold them.

Device 10 can further include a wire for actuating a tissue manipulatorend such an actuating wire can thread through center hole 15 (FIG. 2a )at each link 13.

FIGS. 2a-b illustrate another embodiment of device 10. In thisembodiment, device 10 includes an elongated body 12 (FIG. 2b ) which iscomposed of segments 13 attached to a tissue grasper 29. Each segment 13can be fabricated from an alloy (e.g. stainless steel) or a polymer witha diameter of 2.2 (folded) and 6.6 mm (deployed).

Segments 13 can be interlinked via linkage elements or fixable ormovably mounted on a single long flexible rod or the actuating wireand/or elastic sleeve. Segment 13 shown in FIG. 2a includes alongitudinal opening 15 which can accommodate a flexible rod or tube orthe actuating wire and/or elastic sleeve (not shown). Any number ofsegments 13 can be mounted in a series on the rod or tube. In theconfiguration shown in FIG. 2b , four segments 13 are mounted on a rodor tube to form a deflectable region 23 of device 10. Segments 13include 4 deployable control wire guides 18 having holes 22 for controlwires 24. Wire guides 18 are shown in a delivery (closed) state in FIG.2a and in a deployed state in FIG. 2 b.

Each segment 13 includes two interlocked portions, a proximal portion 17and a distal portion 19. A spring 25 pushes portions 17 and 19 away fromeach other and maintains wire guides 18 closed against segment 13,alternatively, wire guides 18 can be wrapped with an elastic tube thatwould function as a spring to keep guides 18 in side link 13. Controlwires 24 are threaded through holes 22 from the handle of device 10 (notshown) to distal region 21. When control wires 24 are pulled in theproximal direction, portions 17 and 19 of segments 13 are compressedagainst spring 25 and wire guides 18 are deployed radially outward thusdeflecting outward the portion of control wires 24 spanning thedeflectable region.

In order to push out wire guides 18 when compressed, proximal portion 17of each segment 13 includes a four-sided wedge that resides withindistal portion 19 and in contact with (and internal to) the internal endof wire guides 18. When portions 17 and 19 are compressed, the wedgeslides further into distal portion 19 thus pushing wire guides 18outward and out of segment 13.

Once deployed, guides 18 enable a user to pull each side of deflectableregion 23 and thus steer it in any direction. Since the ends of segments13 are rounded, and wire guides 18 of adjacent segments are distancedfrom each other, region 23 can be deflected more than 90 degrees in anydirection. Such deflection can be used to position a tissue grasper 29at anatomically constrained spaces, or loop a device around an organ,for example, loop a gastric band around a lower esophageal sphincter orfundus of a stomach.

FIGS. 3a-c illustrate yet another configuration of device 10 whichincludes discrete segment 13 mounted over a flexible core 31 whichincludes a flexible tube/rod 33 surrounded by a spring like element 35.

Each segment 13 includes a proximal portion 17 and a distal portion 19connected via one or more pivoting linkage arms 37 (Four shown in FIGS.3a-c ) which serve as control wire guides 18.

Control wires 24 run through holes 22 provided through linkage arms 37.When in a delivery state (FIG. 3a ) linkage arms 37 are linearized andlie flat against spring-like element 35, while proximal and distalportions (17 and 19 respectively) are spaced apart. When distal portion19 is pulled against proximal portion 17 linkage arms 37 pivot atmidpoint pivot 41 and endpoint pivots 43 and extend radially outwardthereby distracting control wires 24 away from the longitudinal axis ofelongated body 12. Distal portion 19 can be pulled against proximalportion 17 by pulling on any one of control wires 24 or by pulling aseparate deployment wire or by pushing proximal portion 17 towardsdistal portion 19 using internal tube 47 (shown in FIGS. 2b, and 4a-b ).

In order to enable device 10 to assume a closed state for removal fromthe body cavity, segments 13 preferably include a spring 39 which iscompressed when segments 13 are compressed (during deployment of linkagearms 37), releasing the deployment force (e.g. releasing a pull wire),spaces apart portions 17 and 19 thus returning linkage arms 37 to theirlinearized state.

FIGS. 4a-c illustrate a tissue manipulating device 10 which includes adeflectable region 23 composed of three segments 13 (similar to thoseshown in FIGS. 3 a-c but with 2 wire guides 18 per segment 13). Device10 can be configured as an endoscope, catheter or any otherconfiguration deliverable into a body cavity, a vessel, a tissue and thelike.

Device 10 includes a tissue manipulating head 44—tissue grasper headshown. Head 44 includes linkage mechanism 46, which is actuated via adedicated wire 48, which runs within elongated body 12 to the userhandle.

FIG. 4a illustrates device 10 in a delivery state with linkage arms 37lying flat against elongate body 12 and portions 17 and 19 spaced apart.Following delivery into the body, pulling of control wires 24 or pushinginternal tube 47 (FIG. 2b ) compresses segments 13 and deploys wires 24radially outward (FIG. 4b ). Further pulling of one wire 24 (top wire 24in FIG. 4b ) deflects region 23 towards the pulled wire and may anglesit more than 90 degrees with respect to a longitudinal axis of elongatedbody 12. Deflection is maximized to contact between guides 18 asindicated by 50 in FIG. 4c . The contact between guides 18 is used tokeep the articulated joint in a rigid state both for pulling (againstthe tensioned control wires 24) or for pushing (against the body oflevers 18).

FIGS. 5a-b illustrate a device 10 that employs 8 segments 13 forming 2separate deflectable regions 23 and 23′. Each of regions 23 and 23′ areseparately deflectable via a pair of dedicated control wires 24. A firstpair of control wires 24 terminate at attachment points 52 (the distalmost segment 13 of region 23), while a second pair of control wires 24terminate at points 54 (the distal most segment 13 of region 23′). Thisenables a user to deflect both regions 23 and 23′ in the same direction(FIG. 5a ) enabling 180 degrees or more of deflection, or in oppositedirections (zigzag, FIG. 5b ). The latter enables insertion of thedevice ‘behind’ or around organs such as an intestine.

Thus, the present invention provides a steerable medical device that canbe deployed through standard delivery port and yet provides superiorsteerability especially in tight anatomical spaces while requiring farless activation force to steer.

The medical device of the present invention is particularly advantagesin procedures which require steering through tight anatomical spacesand/or steering around an organ.

As is mentioned hereinabove, control wires 24 of device 10 arepreferably actuated from the user end of device 10 using a handle or ahand held motorized tool.

FIG. 8a illustrates one handle configuration that can be used with thepresent device. FIG. 8b illustrates the handle attached to the proximalend of elongated body 12 which includes a tissue manipulator 44 attachedto its distal end.

FIG. 8a-b show handle 100 and related components. Handle 100 includes ahandle housing 102 that contains shaft housing 104. Shaft housing 104contains flexible core 118 compensating mechanism 112 wires 120 and wireends 122. Wire ends 122 are locked into compensating mechanism 112,through holes located at the circumstance of flexible core 118. Wires120 extend through struts 20 and are locked to an end strut or thedistal end of elongated body 12 or tool tip housing. Handle housing 102and shaft housing 104 forms a ball joint.

Following insertion of device 10 into the body cavity, shaft adapter 106(hingedly locked to handle 102 through locking mechanism 130) isadvanced in a distal direction to deploy struts 20 (to a deployed stateset by the surgeon). Once struts 20 are deployed, compensating mechanism112 moves in order to allow the deployment of the struts, while keepingthe tension in wires 120. The surgeon can then articulate the distaljoint by exerting a force on handle 102 causing the flexible core 118 tobend which causes the pulling of wires on the longer side of flexiblecore 118. The pulled wire pulls the distal end of elongated body 12 andangles elongated body 12. When the surgeon reduces the force on handle102, central elastic element 114 and flexible core 118 return to theiroriginal state. The amount of deflection in flexible core 118 determinesthe pulling force on the control wire and the radius of angulation.

The proximal end of push/pull rod 116 is connected to jaws button 108(mounted on jaws button shaft 140) through pin 110. When the surgeonmoves jaws button 108 forward by sliding on jaws button shaft 140, thedistal end (48, FIG. 4b ) of push/pull rod 116, actuates jaw levers (46,FIG. 4b ) which actuate jaws 44. A spring 124 can be used to facilitatethe forward movement of jaws button 108. Rotating jaws button 108rotates jaws 44 via pin 110 that transfers the rotation movement to thejaws via push/pull rod 116.

Device 10 of the present invention also provides advantages when using amotorized handle to steer elongated body 12 and actuate tissuemanipulator 44. Since the force needed to navigate elongated body 12 issubstantially less than that need in prior art devices a smaller lightermotor that can be easily integrated into the handle can be used.

Steerable medical devices having external control wire guides that aredeployable (as describe above) or preferably fixed in an outwardconfiguration (as shown in FIGS. 6b-c ), can be packed as a system in adelivery tube. Such a system, which is referred to herein as system 10is shown in FIGS. 6a and d ).

By utilizing a combination of two or more device configurations (twotypes shown in FIGS. 6b-c ), two or more devices (five shown in thecross sectional view of FIG. 6a and the isometric view of FIG. 6d ) canbe efficiently packed in a single delivery tube 102. For example, system100 shown in FIGS. 6a and 6d includes one device 10 having 4 rows ofguides 18 and hence 4 control wires 24 (FIG. 6b ), and four of device 10which includes 2 rows of guides 18 and hence 2 control wires 24 (FIG. 6c).

Device 10 having 4 rows of guides 18 can be positioned in the middle ofdelivery tube 102, while the four device 10 having 2 rows of guideseach, can be positioned there around. This maximizes packing of thedevices in delivery tube 102 and enables delivery of several steerabledevices having one or more steering capabilities into a body cavitythrough a standard delivery port.

Devices 10 of system 100 can be used separately, i.e. each can bemanipulated separately, or as is shown in FIG. 6d , devices 10 can becooperatively manipulated (via a single system handle or fivedevice-dedicated handles) to enable tissue manipulation not possiblewith a single device.

Device 10 can be operated using a manual or motorized handle. Oneexample of a manually operated handle is illustrated in FIGS. 8a-babove.

As used herein the term “about” refers to ±10%.

Additional objects, advantages, and novel features of the presentinvention will become apparent to one ordinarily skilled in the art uponexamination of the following examples, which are not intended to belimiting.

EXAMPLES

Reference is now made to the following example, which together with theabove descriptions, illustrate the invention in a non limiting fashion.

Prototype Grasper

The configuration illustrated in FIGS. 7a-e was fabricated using rapidprototype technology (FIGS. 9a-b ). Shaft and links body diameter was 7mm when the struts are folded the tool can be inserted through port withinner canal having 7 mm diameter. When the struts are fully deployed,the distance between the wire and center of the steerable segment is 8mm. The steerable segment was easily articulated (FIG. 9b ) by pullingthe control wires and the tissue grasper end was rotated and actuatedusing a central wire.

It is appreciated that certain features of the invention, which are, forclarity, described in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the invention, which are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany suitable subcombination.

Although the invention has been described in conjunction with specificembodiments thereof, it is evident that many alternatives, modificationsand variations will be apparent to those skilled in the art.Accordingly, it is intended to embrace all such alternatives,modifications and variations that fall within the spirit and broad scopeof the appended claims. All publications, patents and patentapplications mentioned in this specification are herein incorporated intheir entirety by reference into the specification, to the same extentas if each individual publication, patent or patent application wasspecifically and individually indicated to be incorporated herein byreference. In addition, citation or identification of any reference inthis application shall not be construed as an admission that suchreference is available as prior art to the present invention.

What is claimed is:
 1. A medical device comprising: (a) an elongateddevice body, at least a portion of which being steerable within a bodyof a subject via at least one control wire; and (b) a plurality ofcontrol wire guides disposed along said elongated device body, said wireguides being deployable to move radially outward and away from anexternal surface of said elongated device body so as to move said atleast one control wire away from said external surface of said elongateddevice body, wherein movement of said at least one control wire awayfrom said elongated body decreases a pull force required for steeringsaid steerable portion and offsets a longitudinal axis of said at leastone control wire from an axis of deflection of said steerable portion.2. The medical device of claim 1, wherein at least a portion of saidelongated device body is composed of a plurality of segments.
 3. Themedical device of claim 2, wherein said control wire guides form a partof said segments.
 4. The medical device of claim 3, wherein said controlwire guides are attached to said elongated device body via a pivotinghinge and extend radially outward from said external surface of saidelongated device body when said plurality of interlinked segments arelongitudinally compressed.
 5. The medical device of claim 4, furthercomprising a tube for compressing said interlinked segments.
 6. Themedical device of claim 2, wherein said plurality of segments areinterlinked.
 7. The medical device of claim 2, wherein said elongateddevice body includes a flexible tube positioned through each of saidplurality of segments.
 8. The medical device of claim 1, wherein saidcontrol wire guides are attached to an external surface of saidelongated device body via a pivoting hinge.
 9. The medical device ofclaim 1, wherein said control wire guides are struts capable of pivotingaway from a longitudinal axis of said elongated device body.
 10. Themedical device of claim 9, wherein said pivoting of said struts iseffected by pulling of said at least one control wire.
 11. The medicaldevice of claim 9, further comprising a tubular sheath for compressingsaid struts against said elongated device body, wherein removal of saidsheath releases said struts to pivot away from a longitudinal axis ofsaid elongated device body.
 12. The medical device of claim 1,comprising a plurality of control wires, each being for deflecting saidat least a portion of said elongated device body in a specificdirection.
 13. The medical device of claim 12, wherein each of saidplurality of control wires is deflectable via a specific set of controlwire guides of said plurality of control wire guides.
 14. The medicaldevice of claim 13, wherein a number, spacing and/or deflection distanceof control wire guides of said specific set of control wire guidesvaries for each of said plurality of control wires.
 15. The medicaldevice of claim 1, further comprising a tissue manipulator attached to adistal end of said elongated device body.
 16. The medical device ofclaim 15, wherein said tissue manipulator is a grasper, a tissue cutter,or a needle.